Disclosure of interest: I am the Australian importer of Screen Research screens and I have used their product successfully in projects in the UK and USA, before I became the importer for Australia. For obvious reasons I wont comment on Stewart specifically.

The main screen material from SR is ClearPix2, which is a woven cloth (glass fiber thread coated with PVC) that is completely acoustically inert and transparent (AT), THX and ISF certified. The weave is three-dimensional, so it contains air and it is therefore 100% AT. As a result the audio does not get impeded in any way, no comb filtering, etc. The video is 0.97 gain, which means it only looses 3% light in the weave, whereas perf screens (not specific to any brand) can loose up to 10% light in the holes. So, SR screens are very good in my opinion, both for audio and video. That's why we installed a 200" (horizontal) in the DTS Theatre in London, and a 130" at the BAFTA, and several in music recording studios, cinemas, etc. All the usual products, motorised, fixed etc. The one I would recommend for a project right now is a TheatreCurve, CinemaScope screen, with or without masking, for CinemaScope projection (2.35:1) with an anamorphic lens on your pj. Of course all speakers behind the screen, built into a baffle wall as per THX.

Note: so-called 'free-standing' speakers can be built into a baffle wall and will sound a lot better for it. I am not talking about 'in-wall' jobbies. My colleague Anders Uggelberg and I wrote an essay about the benefits of in-baffle and on-wall speakers as compared to those modern, skinny speakers that are so popular right now. You wont believe how bad these skinny freestanding speakers perform compared to baffle/wall mounted speakers. We are looking for a publisher who will use the essay in their magazine or website.

Call the colleagues at Screen Research North America if you want more details about ClearPix2, they have a nice new PDF brochure, see www.screenresearch.com/contact.php, just ask for Lise and say Hi from Gerben.

I am in the process of designing a new home and want to have a dedicated music/home theater room. Can you make recommendation in terms of size and building!

I was thinking 18 x 20 x 10

With the benefit of not having seen your plans, I can just give you ideal sizes: Based on the 18' width, the length should be 22' or 24' if you plan to build in a baffle wall. Height should be 14.4' if you can get away with it. Non parallel walls would be ideal, just studs with two layer plaster board, acoustic quality. Suspended ceiling with bass trap material on top of the tiles. Corner bass traps, absorbers in front 1/3 of room and diffusers in back 2/3 of the room. So far all of this is cheap, standard building materials, just applied correctly. The result is amazing though!

Then a screen, speakers, pj, chairs and you're in business! (This is the expensive bit!)

What are the advantages of having non parallels wall, I can build a room with in a room, should I do all alls walls non parrallel or would only two sides be sufficient?

Non parallel walls cannot create standing waves between them. Most important is the Left and Right wall, each out a few degrees against the centre line. A room in a room construction is perfect for this. Front needs to be perpendicular to the Centre line, the back can be perp as well, but cover with diffusers in that case.

Yet another benefit of a acoustic transparent screen is that you can cover the wall behind the screen with absorbers, which catch all first reflections from that end of the room. Of course only where there are no speakers...

Good integration of audio and video will create the best experience and room design and equipment can only be as good as the weakest link in the chain.